Horsepower-meter stand



Dec. '13, 1927. 1,652,225

I R. B. wAssoN I HORSE POWER METER STAND Fi1ed'Novf14, 1924 ssheets-sheet nwnvma ATTORNEY Dem "1'3, 1927."

. 1,652,225 R. s. WASSON I HORSE POWER mama STAND Filed Nov. 14, 1924 :sSheets Sheet 2 v INVENTOR- hgl'd ,4 TTORNEY Dec. '13, 1927.

' B. WASSON HORSE POWER METER STAND Filed Nov. 14, 1924 3 Sheets- Sheet3 a N t W ing auto cars and a stand by mean supported and tes PatentedDec UNITED STAT My in vention duplicate service One of the ob provide acarrying the floor the tracks together with mounted in the stan incombination r securing the auto car to s disclosed herein is portingwheels, plying especially constr gme testing appa plication, Serial Withthe abov simple, horizontal tracks level and inclined ways leading tosupporting wheels means fo the stand. The apparatu ROBERT B. WASSON, FCRIANFORID, NEW JERSEY.

HORSEPOWER-METER STAN D.

' Application filed November 14, 1924. Serial No. 749,897.

relates to a stand for testupon which the auto rests while being tested.

conditions.

more particularly to such of which the car can be ted under conditionswhich jects of the invent-ion is to transportable ucted for use d anddriven testing stand supported above by the supwith load apwith theenratus of my copending ape and other objects in view,

out hereinafter. ings which lllust invention arts, improvefully pointedFig. 1 is a side elevation of the Stand with a car diagramma and locatedin place Fig 2 1s a plan view 100 for a test.

king down tically illustrated upon it,

upon

the stand with the car removed.

Fig. 3 is a thru one of the brake drum, and

Fig. l is a sid supporting whee dynamometer.

In the drawings, testing device lIlG which may be a have flanged sides3, up between which flanges t auto to be tested align the auto on wheelsmay take orting wheels.

The tracks as ground. In the trated the formed of planks 6; cross thetracks and planks, so as to ls, the b will run. the stand so detailedsectional view passing supporting wheels and the e elevation of'one ofthe rake drum and the the stand for the auto car ludes elevated supportspair of tracks 1, 2, which on which tracks and he wheels 4, of the Thesetracks that the rear their position on the supshown are arrangedhoriform of th cross-pieces 8;

form a firm,

be varied, s at a height above the e invention illustracks are carriedin a stand -pieces port the car, and inclined up which the car runshorizontal tracks. The car run upon the testing stand are provided 7,connect connect the strong stand at 13, so that the rear car wheels l,may rest upon the supporting wheels. The coaxial supporting wheels 12,are connected by, a shaft 14, and the shaft is mounted to rotate inbearings supported on suitable cross-members or braces 15. Means areprovided for positioning and securing the auto to the tracks, with itsrear wheels upon and directly above the. supporting wheels. Said meansprovide the load and permit the rear wheels to deliver their power tothe supporting wheels, also permitting their free lateral oscillation.The supporting wheels are ungrooved and provided with cylindrical facesbroader than the tread of the tire so as to permit slight lateraloscillation of the rear wheels of the auto while under test. Asillustrated, a hook 16 pivoted at 17 to an adjusting slide 18, isprovided, the slide-being connected to the brace piece 20, secured tothe stand. A set screw 21, cooperates with the hook soas to clamp thefront axle 22 of the car in place. Rear hooks 23, are pivoted to thestand and are adapted to be secured around the rear axle housing 24, of

to vary their adjustment and to vary and proper load and tractive effortto the car. The car can thus be securely fastened in place so that itcannot move forward or backward while under test;

By providing one the center of thefront axle which receives the thrustof the two rear wheels, the propelling forces are triangulated asagainst a singlepoint of restraint. This means permits the free lateralslight oscillations of the two driving wheels due to differences infriction between the driving wheels and the drivenwheels, to lack ofparallelism of the two rear driving wheels and other causes. Thisenables the two driving wheels to deliver all their power to the horsepower meter. The two hooks at the rear are so arranged that they do notprevent this lateral give the oscillation within practical limitsf Theirfunction is to increase the pressure between the driving tires and thedriven wheels. They provide the load.

Means, which may be varied, areprovided for measuring the power givenoff by the rear wheels of the auto car under test. In the form of theinvention illustrated,'an ab sorption dynamometer is provided which 1Sconnected to one of the supporting wheels. I As illustrated, a brakedrum 25, is keyed to the shaft 14, which carries the supporting wheels12, so as to turn with the shaft. A

. rope or band 26, is wound one or more times about the brake pulley soas to apply the braking pressure.

One end of the rope, the

; pulling end is connected to lever 27, of the leverage system'of thedynamometer, which transmits the pull to the scale. The free end of therope is clamped upon a pulley 28, by

' a lever clamp 29, having a clamping pin 30.

An arm of the rope. taking up the 31, carrying an adjusting weight 32,is secured to the pulley 28, and turns it, so as to take up the slack inthe attached end The clutch pulley 28 permits slack of the rope and alsopermits the angular adjustment of the weight lever, which in turn,controls its moment and pull on the rope. justment of the weight tobalance the pull of the motor and in this case the stand requires no'attendant during the running in.-

A clamping arm 33, operated by handle 34, may be used to lock the ropeor band while adjustments are being made. When a horsepower test isbeing made, the weight is adjusted so as to merely take up the slack ofthe rope without exerting a substantial pull thereon. The weight arm maybe set at an angle below the horizontal and will act as a governor tocontrol the friction of the rope on the brake pulley, being pulledtowards horizontal when the friction changes."

Means are provided for measuring the pull provided by the rotating brakewheel and in the best embodiment of the invention I employ a pluralityof reduction levers for transmitting the pull to the scale 35. Lover 27is connected to the pulling end of the rope or band and at the otherendof 27 is connected by link 37 to lever 36, which in turn is connectedto a scale 35. Meansare provided for making the reading direct, i. e. sothat the operator may, by multiplying the scale reading by thetachometer reading and dividing by one thousand,

at once obtain the horse power that is being absorbed. As illustrated,the circumference of the brake drum is in a predetermined definiterelation to the reductive value of the dynamometer linkage, and is alsoin definite fhorsejpowe'r dividing fQI'IlhSlIOWII and the It thuspermits an ad-' of the dynamometer brake drum is chosen asthirty-threefeet divided by eight or four feet one and one-half inches; The scalereading of scale 35, in pounds, therefore, when multiplied by two andone-half and multiplied by the tachometer reading (giving the number ofrevolutions of the brake drum) and the result divided by three decimalplaces) will give the horse power developed. When measuring the horsepower of heavy truck engines, the dy namometer leverage of twenty to oneis preserved, but when measuring smaller horse power as of pleasurecars, the fulcrum of the lever 36, is moved to the right (point 38*) soas to make the reduction of the lever one to two. The reduction factorof the lever thus becomes one to eight and horse power may be readdirect-by merely multiplying the scale reading by the tachometer readingand dividing by one thousand. Or an intermediate pivoting of lever 36may be utilized. balancing weight 39, is used movable on the end oflever 36, to balance the weight of the lever 36, lever 27 andthe pullingend of the rope so as to bring the scale 35, to zero. A dashpot ver .36,and moving in the liquid filled dashpot 41, is connected to lever 36, byrod 42. This dampens the oscillations of the dynamometer linkage.

The brake drum is cooled to prevent charring the rope. Wateris fed tothe interior of the drum'thru pipe 44. The water discharges from thedrum thru scoop-pipe 46, having a packing joint 45, with the drum, intoa pail so that the flow of water may always be observed.

The tachometer 50, is preferably driven from a gear 51, which is carriedby the brake shaft and intermediate gear 52, and flexible shaft 53, thetachometer giving directly the number of turns per minute of the shaft14.

Having thus described the the operation of testing a car ing' stand,will be clear. transported and setup in a place on a level floor. Thecar runs up the inclined ways to the horizontal supporting tracks and isfastened down upon the stand with an adjusted load upon the rearsupporting wheels. The scale is adjusted to zero "by shift-ing the upperbalance weight. The car is driven construction, on the test- The standmay be at the desired speed and the operator maone thousand; (i. e.pointing off piston 40, connected to le-. I

Having thus described the invention, it will be understood that changesmay be made in the construction for carrying the invention into effect,without departing from the principle thereof.

What I claim is:

1. An auto 'car testing device comprising in combination, a standincluding a pair of tracks, means for supporting said tracks above thefloor level and inclined ways lead ing to said tracks, a pair ofsupporting wheels mounted insaid stand beneath said tracks, anabsorption dynamometer carried by said stand and driven by saidsupporting wheels and load-applying means for securing the auto car tothe stand with its rear wheels upon and above the said supportingwheels, said means being constructed to permit variation of the loadapplied to the supporting wheels.

2. An auto car testing device comprising in. combination a support forthe car, a pair of supporting wheels, an absorption -dynamometer drivenby said supporting wheels means for securing the front of the car to itssupport, and load-applying means for securing the rear of .the auto carto itssupport the car being thus positioned, with its rear wheels uponand above the said supporting wheels, said load applying means applyingthe load to the supporting wheels.

3. An auto car testing device comprising in combination a standincluding a pair of tracks, means for supporting said tracks above thefloor level and inclined ways leading to'said tracks, a pair ofsupporting wheels mounted in said stand beneath said tracks, anabsorption dynamometer carried by said stand and driven by saidsupporting wheels, and three hooked members, one carried by the front ofthe stand and two carried by its rear portion for securing the auto tothe stand with its rear wheels upon and above the said supportingwheels.

4. An auto car testing device-comprising in combination, a standincluding a pair of tracks, legs for supporting said tracks above thefloor level and inclined ways leading to said tracks, a supporting wheelmounted in said stand beneath one of said tracks. a dynamometer driven)y said supporting wheel means for securing the front of the car to thestand, and load-applying means for securing the rear of the auto car tothe stand, one of its rear wheels resting upon and above'the saidsupporting wheels, said load applying means applying the load to thesupporting wheel.

5. An auto car testing device comprising in combination a standincluding a pair of tracks, legs for supporting said tracks above thefloor level, one pair of legs at the front and two pairs at the rear ofthe stand, and inclined ways leading to said tracks, a pair ofsupporting Wheels mounted in said stand porting wheels,

beneath said rails and betweenthe two pairs of rear legs, a dynamometerdriven by said supporting wheels, load applying hooks pivotcd to therear of the stand for securing the auto car to the stand with its rearwheels upon and above the said supporting wheels, said hooks applyingthe load to the sup porting wheels, and permitting lateral oscillationof the rear wheels of the car upon the supporting wheels.

6, An auto our testing device comprising in combination, a standincluding a pair 0 tracks, means for supporting said tracks above thefloor level, and inclined ways leading to said tracks, a pair ofsupporting 'heels mounted fin'said stand beneath said tracks, a brakewheel riven by said supporting wheels, a flexible strap coiled aboutsaid brake wheel, means for clamping one end of said strap, a weight forpulling upon said clamping means, a dynamometer lever *arried bythe'stand, means for securing the other end of the strap to said lever,a scale, and means for transmitting the pull of said lever exerted bythe strap to said scale.

7. An auto car testing device comprising in combination a standincluding a pair of tracks, means for supporting said tracks abovethe-floor level, and inclined ways leading to said tracks, a pair ofsupporting wheels mounted in said stand beneath said tracks, a brakewheel driven by said supa flexible strap coiled about said brake wheel,means for clamping one end of said strap, a weight for pulling upon saidclamping means, a dynamometer lever carried by the stand, means forsecuring the other end of the strap to said lever, a scale, a secondlever connected to the first lever, and means for connecting said secondlever to said scale.

8. An auto car testing device comprising in combination, a standincluding a pair of tracks, means for supporting said tracks above thefloor level and inclined ways leading to said tracks, a pair ofcylindrical sup porting wheels mounted in said stand beneath saidtracks, a brake wheel carried by said stand and driven by said wheels, astrap coiled about said brake wheel, a scaleand a reduction linkagecarried by the stand, one end of the linkage being connected to saidstrap, the other. end of the linkage being connected tosaid scale, thecircumference of the brake drum bearing a predetermined re lation to thereductive value of the said linka e. y

9. n auto car testing device comprising in combination, a standincluding a plurality of longitudinal planks, a pair of tracks, one varranged between each pair of planks, crosspieces connecting the tracksand cross-pieces connecting the planks, thereby forming a stand uponwhich the auto car rests While being tested, inclined Ways leading tosaid above the floor level, a pair of cylindrical supporting wheelsmounted in said stand beneath said tracks, a dynamometer driven by saidsupporting wheels, and load applying means for securing the auto car tothe stand with its rear wheels above and upon the said supportingWheels.

10. Anauto car testing device comprising in combination a standincluding a pair of tracks, means for supporting said tracks above thefloor level, and inclined ways leading to said tracks, a pair ofcylindrical supporting wheels mounted in said stand beneath said tracks,a brake Wheel driven by said supporting wheels, means for cooling thebrake wheel, a flexible strap coiled about said brake wheel, means forclamping one end of said strap, a weightgfor pulling upon said clampingmeans, a dynamometer lever carried by the stand, means for securing theother end. of the strap tosaid lever, a scale, and means fortransmitting the pull of said lever exerted by the strap to said scale.

11. An auto our testing device comprising in combination, a standincluding a pair" of tracks, means for supporting said tracks above thefloor level, and inclined ways. leading to said tracks, a pair ofcylindrical supporting wheels mounted in said stand beneath said tracks,a brake wheel driven by said supporting wheels, means for supplyingwater to the interior of and discharging it from said brake Wheel so asto cool it,-a

flexible strap coiled about said brake wheel,

inclined ways provided with flanges, leading to said tracks, a pair ofcylindrical support-- ing Wheels mounted in said stand beneath saidtracks, an absorption dynamometer carried by said stand and driven bysaid supporting wheels and load-applying means for securing the auto carto the stand with its rear wheels upon and above said sup portingwheels, said means applying the load to the supporting wheels.

In witness whereof, I have signed my name to this specification.

ROBERT B. WASSQN.

